Virtual-machine technology essentially abstracts the hardware resources and interfaces of a computer system on behalf of one or multiple virtual machines, each including one or more application programs and an operating system. Cloud computing services can provide abstract interfaces to enormous collections of geographically dispersed data centers, allowing computational service providers to develop and deploy complex Internet-based services that execute on tens or hundreds of physical servers through abstract cloud-computing interfaces.
Managing and troubleshooting customer data centers which include virtual servers as well as physical servers, virtual machines and virtual applications is often quite difficult. Moreover, any downtime associated with problems in the data center, or components thereof, can have significant impact on a customer relying on the data center.